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''Photinus pyralis'', known by the common names common eastern firefly〔(Animal Pictures Archive )〕 and big dipper firefly, is the most common species of firefly in North America.〔(State Symbols USA: Tennessee State Insect )〕 ''P. pyralis'' is a flying and light producing beetle with a light organ on the ventral side of its abdomen. This organism is sometimes incorrectly classified as ''Photuris pyralis'', which likely results from mistaking the similar sounding genus ''Photuris''. The ''Photuris'' female may also lure a ''Photinus pyralis'' to be eaten to obtain spider-repellent steroids which Cornell researchers named "lucibufagins" in 1997.〔Roger Segelken (Lured and liquidated, gullible male fireflies supply 'femmes fatales' with a lifesaving chemical ) ''Cornell Chronicle'' September 1, 1997. Retrieved November 22, 2012.〕 In males the light organ covers the entire ventral surface of the three most posterior segments and in females it only covers a portion of the third posterior segment.〔Mast, S.O. 1912. Behaviour of fire-flies (Photinus pyralis) with special references to the problem of orientation. 256-272〕 These fireflies are most noticeable around twilight, in the early part of the evening and hover close to the ground.〔Rau, P. 1932. Rhythmic periodicity and synchronous flashing in the firefly, Photinus pyralis, with notes on Photurus pennsylvacicus. Ecological Society of America, 13:7-11〕 The species' common name refers to the characteristic flight of the male, which flies in a J-shaped trajectory, lighting on the upswing. During flight, the J-shaped flight pattern is used in combination with patrolling flash patterns while seeking a mate.〔Case, J.F. 2004. Flight studies on photic communication by the firefly Photinus pyralis. Integrative and Comparative Biology, 44:250-258〕 Their flashes are stimulated by light conditions, not by rhythmic impulses as originally thought 〔 ==Light production== Males of ''Photinus pyralis'' locate females by a series of light flashes, to which females respond with a coded delay flash. The light organ of ''P. pryalis'' is composed of two layers; a layer of refractile cells on the dorsal side and a photic layer with light producing cells on the ventral side.〔Beams, H.W. and Anderson, E. 1955. Light and electron microscope studies on the light organ of the firefly (''Photinus pyralis''). The Biological Bulletin, 375-393〕 The light organ (specifically the photogenic layer) is supplied with numerous tracheal branches, which are thought to provide the required oxygen for light production.〔 The light producing enzyme is luciferase, and is found within cells of the lantern.〔Keller, G.A., Gould, S., Deluca, M. and Subramani, S. 1987. Firefly luciferase is targeted to peroxisomes in mammalian cells. Proceedings of the National Academy of Sciences, 84:3264-3268〕 Luciferases require oxygen, luciferin and adenosine triphosphate (ATP) to catalyze a chemical reaction that produces bioluminescence in these insects.〔() 〕 It has been shown that the glow is not controlled by the tracheal end cells (which were thought to contain valves) nor by central nerve impulses through studies involving low oxygen conditions.〔Hastings, J.W. and Buck, J. 1965. The firefly pseudoflash in relation to photogenic control. The Biological Bulletin, 101-113〕 Pupae of these beetles have different light organs than the adult. They do not have the characteristic tracheal end cells of the flashing adults, and whereas the adults emit bright flashes, pupae emit low intensity glowing.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Photinus pyralis」の詳細全文を読む スポンサード リンク
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